1. Field of the Invention
The present invention relates to a motorized tilting device according to the preamble of the main claim.
2. Brief Description of the Background of the Invention Including Prior Art
A device of this type is known from German Patent Application 35 01 454 A1 as a drive for transforming a rotational movement into a translational movement. For this purpose, a worm engages in threaded profiles on the surface of a band made of elastic material, which is guided in the longitudinal direction so that it may have pressure applied to it and is deformable transverse to its broad side. The guide runsxe2x80x94coming out of a linear railxe2x80x94past the worm engagement in large curves around the worm and the drive motor, which is oriented coaxially thereto and with the worm parallel to the band, and back into the rail. A slide is connected there to one of the two free ends of the band, in order to traverse it along the guide rail and thus move a gate. However, stable mounting and vibration-resistant adjustability of the spatial angle of a support plate for an outside mirror of a truck, for example, cannot be implemented using a slide guide which occupies so much space.
In German Patent Application 33 11 229 A1, the combination of a slider crank drive for a pitching movement with a further drive for converting a rotational movement into a longitudinal movement is provided, behind a shared drive motor, especially for mirror adjustment, but also for adjusting seats and steering wheels in vehicles, for example, in such a way that a rapid pitching movement is superimposed on a slow pivoting movement. To tilt the support plate around a vertical shaft end, a pull rod, which is periodically displaced lengthwise due to an elastic engagement of its opposite end in a rotating worm gear, is linked onto the rear of the plate. Simultaneously, the crank mechanism, which is also linked to the back of the plate, generates an oscillating movement. However, precisely because of the restriction to one single motor shared by both of the movement axes, this represents an adjustment device whose mechanism is very complicated, and which is not vibration resistant due to its many linkage points.
A tilting device of another species is known from European Patent Application 0 316 055 A1 in the form of a housing to receive one reversible small electric motor each for the coordinated drive of each of two tappet-like linear actuators, which may be extended out of the housing and/or withdrawn therein opposite to one another. In this way, they tilt a support plate around an axis centrally transverse to the connection line between the two linear actuators. The requirement of having to simultaneously use two motorized drives acting oppositely coordinated for this simple pivot movement of a mirror support plate around a pivot axis is, however, very costly. In addition, the operational reliability is impaired due to the danger of not exactly synchronized operation; if the two linear actuators are not moved exactly opposite by their motors, then a reproducible tilting movement of the support plate around a predetermined fixed geometric axis does not occur, but rather this pivot axis experiences a lateral displacement.
3. Purposes of the Invention
The present invention is based on the technical problem of designing a tilting device, particularly for the support plate of a truck outside mirror, with lower outlay for individual parts and more functional robustness, at least in regard to reproducible and vibration-resistant adjustability.
This object is achieved according to the present invention in that, according to the essential features indicated in the main claim, the motorized pivot movement for each pivot axis of the plate is performed using at least one adjustment rod, which, on both sides of a linear, toothed central region, on which a motor pinion engages, turns into a curved region, which may have tension or pressure loads applied to it like the central region due to its material selection or its constructive guide. These adjustment rods, which comprise different regions and are only necessarily toothed in their central region, are therefore not necessarily toothed rods which are constructively costly since they are continuously flexible per se.
The support plate is preferably centrally, e.g., spherically, mounted on its back side, opposite its mirror surface, on the housing. The flexible regions of the adjustment rods on both sides of the linear toothed rod regionxe2x80x94mounted in the housing so it is longitudinally displaceable approximately parallel to the support plate by the adjustment motor via a reduction drivexe2x80x94each first run into the housing through a curved guide and then out of the housing to the support plate supported in front of it, onto whose back side they are linked using their front ends. If the motor displaces the toothed region to tilt the mirror plate, a flexible region of the adjustment rod is therefore subjected to a tensile load and the opposite region is subjected to a compressive load.
Both of the flexible regions on both sides of the central (toothed) section of the rod preferably turn, before their free front ends, back into stiff end pieces, which pass through a linear guide as they exit out of the housing and then are linked onto the back of the support plate at two pointsxe2x80x94which are diametrically opposite one another in relation to the mounting of the plate on the housing. For this linkage, the technology of snap connections having spherical overlap surfaces as joints for movement transmission may be used, as may be produced without problems and with functional reliability in plastic injection molding.
A similar adjustment rod, which is driven by a motor in its toothed central region, may be aligned transverse to the first mentioned, in order to be able to carry out the pivot movement of the spherically mounted plate around two axesxe2x80x94and also with simultaneous superposition in any arbitrary spatial direction.
In any case, as the plate is tilted around an axis, one half of the adjustment rod, which is curved, is subjected to a compressive load and its opposing half is subjected to a tensile load, which ensures a pivot drive able to be subjected to high mechanical stress and operating without vibration or pinching, at least if the plate is tiltable around a constructively defined point of rotationxe2x80x94due to its spherical linkage mounting on the housingxe2x80x94and is broadly supported on two further points at a distance to one another via the end pieces of the respective rods. Therefore, according to the present invention, in a stably operating tilting device, particularly for the support plate of a motor vehicle outside mirror adjustable by a motor, the plate is mounted using an articulated joint on a housing which is to be mounted in a fixed location, in which a drive motor is positioned, for each of the two orthogonal pivot directions (which may also be superimposed into any desired spatial direction), which engages with a longitudinally movable adjustment rod which is toothed in at least some regions and flexible in at least some regions. This rod is deflected, on both sides of its central toothed section, in curved guides out of the plane parallel to the plate into the transverse direction in order to exit out of the housing, where its end piecesxe2x80x94after bridging the mounting distance between the housing and the platexe2x80x94are connected using an articulated joint to the back side or the inside of the plate to transmit pushing and pulling movements at their faces.
For a more detailed explanation of the present invention and its alterations and refinements, reference is made to the sub-claims and the following description of a preferred exemplary embodiment of the achievement of the object according to the present invention, which is shown in the drawing not entirely to scale and abstracted to the elements essential to its function. The single figure of the drawing shows a cross-section of a housing, to be mounted fixed on object, for the tilting device for tipping a support plate in all spatial directions.